A detail from the painting of publisher Gail Rebuck by Scottish artist Jennifer McRae.
Photograph: National Portrait Gallery

A portrait of one of the most influential figures in British publishing, Gail Rebuck, chair and former chief executive of the Penguin Random House group and a co-founder of World Book Day, is being unveiled at the National Portrait Gallery in London.

Rebuck, a Labour peer since 2014, said she was “unusually speechless” when asked about being added to the collection.

The final image, by the award-winning Scottish painter Jennifer McRae, who already has several portraits, including one of the writer Michael Frayn in the collection, shows Rebuck against a packed bookshelf, with her desk scattered with books, a notebook and her Kindle. In the background are two favourite views, the rooftops outside her London office and the favourite view of their home of her late husband, Lord Gould – better known as New Labour adviser Philip Gould.

Rebuck said she had come to see the similarities between the artist’s blank canvas and the empty pages her writers faced: “Jennifer’s portrait is full of detail and our ‘in jokes’ as we got to know each other over a year of sittings. I came to appreciate the skill of portraiture – the blank canvas so similar to the blank page as a writer begins their work. I am full of admiration.”

McRae described her subject as “a handsome and strong woman with self-deprecating charm and intelligence, who also happens to be at the centre of the publishing world and rather brilliant at her job”.

The NPG director, Nicholas Cullinan, called it “a thoughtful portrayal of one of Britain’s most influential publishers”.